Rotary devices, particularly rotary heat exchangers



Jan. 31, 1961 H. R. NILSSON ETAL 2,969,958

ROTARY DEVICES, PARTICULARLY ROTARY HEAT EXCHANGERS Filed March 14, 19553 Sheets-Sheet 1 J at m,

Jan. 31, 1961 H. R. NILSSON ETAL ROTARY DEVICES, PARTICULARLYROTARY HEATEXCHAN 14, 1955 3 Sheec, sheat 3 Filed arch n o n n x x Q o r o x o oROTARY DEVICES, PARTICULARLY ROTARY HEAT EXCHANGERS Hans Robert Nilsson,Ektorp, and Per Walther Sigvard Persson, Johanneshov, Sweden, assignorsto Svenska Rotor Maskiner Alrtiebolag, Nacka, Sweden, a corpuration ofSweden Filed Mar. 14, 1955, Ser. No. 494,908 27 Claims. (Cl. 257-267)The present invention relates to rotary devices and more particularly tosuch a device including a rotary structure adapted for anti-frictionmounting at its periphery.

The general object of the invention is to provide a rotary device havinga rotor comprising an assembly of a plurality of units, which are easyto transport from the factory to the site of the use of the apparatus,wherein the rotor forms a component and which units are readily securedin the integral rotor in which the units are replaceable with a minimumof inconvenience and labour.

According to the present invention a rotor device comprises a rotorcomponent, a stationary component and bearing means for rotatablysupporting the rotor component at the outer periphery thereof withrespect to'the stationary component, said rotor component comprising aplurality of sector or wedge shape baskets positioned in abuttingrelationship around the centre of the rotary device so that the radialsides of contiguous baskets define partitions extending radially fromthe inner to the outer periphery of the rotor component and the innerand the outer walls of the rotor component comprise abutting transverseends of abutting baskets.

The wedge shaped baskets are fastened together with suitable joiningmeans such as bolts or rivets fastening the baskets together along themarginal portions of the abutting radial side walls of the baskets sothat a coherent rotor component thus is formed thereby which may besuspended on or carried by the bearing means provided for rotatablysupporting the rotor component at the outer periphery thereof.

In another form, the rotor device according to the invention comprisestwo superimposed portions, a first portion of which comprises astructural plate framework suspended on or carried by the bearing meansand the second portion of which comprises a structure made'up of basketunits fastened together, said basket structure being suspended from orcarried by the structural plate framework.

It is an additional object of the invention to provide an attachment forrevolving the rotor equipment which will provide the equipment with aball bearing assembly on which the rotor is carried by its own weightand on which the same can be operated and wherein one of the racesincludes a pin rack or similar means While the other race serves as asupport for connecting the assembly to the stationary component of therotary device and Wherein access readily can be had to the interior ofthe race members for the removal or changing of the ball bearings.

Other additional objects of the invention are to provide a ball bearingassembly on which the rotor weight is carried by means of peripherallyspaced carrying means extending radially from the rotor, means furtherbeing provided to distribute the rotor weight to as many balls aspossible around each place of contact between each rotor carried and therace upon which the latter rests and to increase the number of theplaces of contact of the forces from the rotor weight along thecircumference of nited States Patent the ball bearing assembly. Stillother objects are to provide a self centering of the rotor upon the ballhearing assembly and to provide means for fixing the rotor and rotatablebearing race peripherally in relation to each other and to provide forrelative radial movements between the rotor component and the respectiveraces of the ball bearing assembly, coaxial relationship between therace and the rotor and full registering between both the races stillbeing maintained. Another object is to provide an attachment for arevolving rotor equipment which is inexpensive to manufacture, easy toinstall and remove or replace and efiicient in operation.

The invention is particularly adapted for heat exchange apparatus of therotary type in which heat exchange between two gaseous fluids is carriedout for purposes such as the preheating of air to be used forcombustion, by waste heat extracted from combustion gases exhausted fromapparatus such as power boilers. The invention will therefore bedescribed hereinafter, by way of example but without limitation, asapplied to air preheating structure, but it will be understood that theprinciples of the invention are susceptible of use in many otherapplications and that for certain of such applications, the principlesof the invention in its broader aspects may be carried out with onlycertain features of the structure hereinafter described in connectionwith the air preheater apparatus chosen by Way of example.

For a better understanding of the more detailed nature of the invention,the manner in which it may be carried out and the advantages to bederived from its practical use, reference may best be had to the ensuingportion of this specification, taken in conjunction with theaccompanying drawings illustrative by way of example but withoutlimitation, of different examples of construction embodying theprinciples of the invention.

In the drawings:

Fig. l is a vertical central section taken on line 1--1 of Fig. 2, of arotary regenerative heat exchanger embodying the principles of theinvention.

Fig. 2 is a top plan view taken on the line 2-2 of Fig. l, partly insection, of the heat exchanger shown in Fig. 1.

Fig. 3 is a partial vertical central section, similar to Fig. l, ofanother form of a regenerative heat exchanger in which the basketassembly is carried by a structural plate framework.

Fig. 4 is a fragmentary horizontal section taken on line 44 of Fig. 3.,

Fig. 5 is a fragmentary horizontal section taken on line 55 of Fig. 3. a

Fig. 6 is a partial sectional view, similar to Fig. 3, of another formof a regenerative heat exchanger in which the basket assembly issuspended from a structural plate framework.

Fig. 7 is a fragmentary section on enlarged scale of a suspension of thebaskets from a structural plate frame. work such as shown in Fig. 6.

Fig. 8 is a fragmentary vertical section on enlarged scale of a form ofstructure for supporting the rotor on the bearing means.

Fig. 9 is a fragmentary horizontal section, similar to Fig. 6, of amodified arrangement of the means for peripherally supporting anddriving the rotor.

Referring now more particularly to Figs. 1 and 2 of the drawings, thereis illustrated one suitable form of preheater for carrying the inventioninto effect. The app-aratus shown comprises a stationary outer casingstructure, indicated generally at 10, having spaced end plates 12 and 14between which the rotor is mounted. Plate 12 is provided with two sectorshaped openings or ports 16 and 18 located generally on opposite sidesof a diametral plane through the rotor. These ports are connectedrespectively with ducts 20 and 22 for conducting one of the heatexchanging fluids to the rotor and the other fluid from the rotor. Plate14 is likewise provided with sector shaped ports 24 and 26, alignedrespectively. with ports 3.6 and 18 in plate 12' and communicatingrespectively with ducts 28 and 30 for conducting the first mentionedfluid from the rotor and said other fluid to the rotor. Countercurrentflow of the two fluids provides for most efficient heat transfer and inaccordance with that practice the apparatus illustrated isadvantageously connected so that, for example, cold air to be heated isadmitted through duct 28 and port 16 to the top of the rotor and afterbeing heated is' discharged therefrom through ports 24 and 28, asindicated by arrow 32, while hot gas to be cooled enters through duct 30and port 26 to flow upwardly through the rotor and be discharged in thedirec tion of arrow 34 through port 18 and duct 22. With suchconnections it will be evident that the upper end of the apparatus towhich fluid to be heated is admitted and from which cooled fluid isdischarged will be referred to as the cold end, the opposite end beingreferred to as the hot end. It will be obvious that either the upper endor the lower end may be the cold end, so long as counter current flowrelation is maintained depending upon which ducts are connected to thesources of supply of the different fluids.

The rotor is circumferentially enclosed and supported by portions of thestationary structure extending between the end plates, which structurein the present example includes a number of peripherally spacedstandards 36 adapted to rest on suitable supporting beams 38 andconnecting in rigidly spaced relation a cylindrical shell 40 whichadvantageously is of relatively thin section because of weightconsiderations, the weight of the rotor being carried primarily by thestandards 36. The shell 40 is connected to a lower ring 42 to which endplate 14 is secured and an upper ring member 44, which constitutes thelower bearing member of a bearing indicated generally at 46 and havingan upper bearing member indicated generally at 48 carrying the rotor.The nature of bearing 46 will later be described more in detail.

Member 44 supports a ring 50 of channel section which in turn supportsthe upper end plate 12. For reasons hereinafter appearing, ring 50 isadvantageously formed by a plurality of segmental elements secured tothe structure by bolts, studs or the like separately removable.

From the foregoing it will be apparent that the shell 40, member 44 andring 50 provide a circumferential casing structure encircling the rotor,and that this structure to gether with the end plates provides astationary structure encasing the rotor and providing means forsupporting it. This stationary structure provides one of the twoprincipal components of the apparatus.

The other principal component is the rotor, indicated generally at 52,which according to a basic feature of the present invention comprises aplurality of sector shaped baskets 54 positioned in abuttingrelationship around the centre of the rotary device so that the radialsides 56 of contiguous baskets define partitions extending radially fromthe inner to the outer periphery of the rotor component and the innerand the outer walls 58 and 60, respectively, of the rotor compriseabutting transverse ends of abutting baskets. The baskets are connectedto form an integral annular rotor member by fastenings such as bolts orrivets 62 joining the radial side walls 56 along the marginal portionsthereof. It is a characteristic of the invention that the basketsof therotor solely by such fastening together form a coherent central rotorcomponent and that the usual rotor post may be completely dispensedwith.

Each of the baskets are filled with regenerative heat exchangingmaterial such as plates 64 mainly vertically disposed and mutuallyspaced in accordance with well known practice which plates "rest uponsuitable supports such as radial bars 66 anchored at the bottom of thebaskets for supporting the heat transferring material.

In the construction illustrated in Figs. 1 and 2, the rotor component issuspended from the bearing device 46 and for this purpose each of thebaskets 54 is provided with radially extending bracket means or fins 68adjacent each radial side 56 of the basket. By means of such fins 68resting directly upon the upper rotatable bearing member 48 the rotor 52may be carried by means of said rotatable bearing member and as theweight of the rotor 52 may be considerable in many instances no furthermeans are necessary to attach the rotor to the rotatable bearing member48 but the rotor simply rotating with the rotatable bearing member atthe turning of the latter due to frictional engagement between thecarrying fins 68 and the rotatable bearing member 48.

The regenerative preheater shown in Figs. 3 to S has a stationary casingstructure in which the bearing device 46 is located at the lower endthereof in order to carry the rotor component by the upper rotatablebearing member 48. The shell 40 of the casing is connected at its topend to an upper ring member 7 0 to which end plate 12 is secured and atits bottom end to a lower ring member 72 which in turn is secured to thering 50 of channel section. The ring 50 is formed by a plurality ofseparately removable segmental sections fastened to the end plate 14.The lower stationary member 74 of the bearing device 46 is also securedto the end plate 14.

The rotor component indicated generally at '76 comprises twosuperimposed portions 78 and 80, the lower portion 78 of which comprisesa structural plate framework made up of T-shaped beams united forinstance by welding into the form of a polygonal spoke wheel 78 in whichthe ends of the spokes 82 extend beyond the outer periphery of the rotoras bracket means 84 to carry the rotor upon the rotatable member 48 ofthe bearing 46. The upper portion of the rotor comprises an assembly ofsimilar wedge shaped baskets 54 as just described above and united bybolts or rivets along the marginal portions of their contiguous radialside walls 56 and at least the basket structure of both of the rotorportions are filled with heat transferring material. The hub and rimportions 86 and 88, respectively, of the spoke wheel register with innerand outer walls 58 and 68 of the basket structure of the rotor and thespokes S2 of the wheel 78 register with the radially extendingpartitions of the basket structure formed by the contiguous radial sidewalls 56 of the baskets, and the basket structure 80 is carried by thespoke wheel 78 on which it may rest simply by its own weight. The opensectors between the spokes 82 may be bridged by chord like bars 98 onwhich the heat regenerative plates 64 are sustained.

'In the air preheater shown in Fig. 6 the position of the spoke wheel 78and the basket structure 80 is reversed in relation to that of the airpreheater just described, the basket structure being suspended from thespoke wheel which latter in its turn is carried on the upper rotatablebearing member 48 of the bearing 46. The construction of the'casing issubstantially the same as described in connection with the apparatusshown in Figs. 1 and In order to avoid repetition, any further detaileddescription thereof is omitted, the corresponding parts being designatedby like reference characters.

Fig. 7 shows one of the simple ways in which the basket structure may besuspended from the spoke wheel. To the lower edge of beam 92 forming aspoke 82 of the wheel 78 is secured-for instance by weldinga horizontalbar 94 to which the upper margins of contiguous radial side walls 56 ofthe baskets are fastened by means of angles 96 and bolts 98.

In accordance with a basic feature of the present invention the rotor isrotatably supported at its periphery by the bearing device 46, ratherthan at or adjacent to its centre'or axis of rotation, the manyadvantages of peripheral support hereinafter to be pointed out beingsecured by the provision or bearing construction the nature and functionor which enables the practical and economical aPPllCaUOH or peripheralsupport to be obtamed mexpenslvely and not omy with a tong life factorbut also with relative ease of repair and replacement when wear doesoccur.

For further description of the bearing construction reference may be hadto Fig. 8 which shows the bearing on emarged scale. The rotor is or thesame nature as that of the construction snown in rigs. l and 2 outcarried at its lower end by means of radial extensions 100 of the radialside walls 56 themselves or the baskets, said extensions forming fins orlugs which carry the rotor supported on the bearin The lower bearingmember 74 is provided with a loadcarrying raceway 102 in the form of anannular recess and preferably so that the lower bearing member is madeup of a number of segments each providing a segmental section of theannular recess 102 in the corners of which are located arcuate lengthsof wire 104 providing lower rails upon which a multiplicity of balls 106may roll.

The number of lengths or sections of wire in each circumference may varyand if desired each rail may consist of only one piece. The jointsbetween adjacent ends of wire should however be staggered.

The upper bearing member 48 may comprise a rigid ring but in a preferredconstruction the same is comprised of a plurality of arcuate elements108 each providing a segmental section of an annular recess 110 formingthe upper raceway for the balls 106 registering with the lower raceway102. The arcuate elements 108 carry pins 112 which form the teeth of aperipheral rack with which the driving gear 114 for turning the rotormeshes. Additional arcuate lengths of wire in the corners of recess 110provide upper rails engaged in rolling contact by balls 106, the latterbeing held in evenly spaced relation peripherally by the retainer 116which is also advantageously in the form of a series of separatesegmental elements.

As in the case of the lower rails, the joints in the upper rails shouldbe staggered both with respect to each other and also with respect tothe joints in the lower rails, so that no ball passes over more than onejoint at a time.

The rotor during the operation becomes hot and expands radially relativeto the housing. The brackets or fins 68, 84 or 100 which carry the rotorare free to slide radially upon the upper rotatable bearing member 48but particularly in rotor constructions of very large diameter due toheat conducted to the upper bearing member the same will increaseconsiderably in width so that the exact registering between the races inthe upper and lower bearing members would be affected. In order to avoidthe differential expansion between the upper and lower hearing membersdue to temperature difference it is advisable to make at least one ofthe bearing members, for instance the rotatable bearing member, ofrelatively movable segments 108 permitting radial enlargement andcontraction of the rotatable bearing member while still retaining thecoaxial alignment of the bearing tracks.

The plurality of ring segments 108 are independently movable in radialdirection relative to the rotor brackets or fins 68, 84 or 100 andindividually guided thereto in a manner which will be described below.Generally at least one carrying bracket 68, 84 or 100 is brought toregister with each ring segment 108, the latter being fixed peripherallyin relation to the rotor, such mutually fixed peripheral relationshipbeing effected by means of the carrying brackets or fins 68, 84 or 100.

However, as it is not possible in practice to manufacture the preheaterwith suificient precision for all the carrying brackets or lugs to makecontact with the rotatable bearing member 48, in the constructions shownresilient means in the form of arcuately upwardly bent plate springs 118are provided between each bracket or fin 68, 84 or 100 and the rotatablebearing ring 48. Such a plate spring is designed for instance so thatthe same permits a springing from 1 to 2 mm. Besides the advan: tage ofa more even force distribution on the bearing ring 48 these resilientmeans 118 resting at both their ends on the rotatable bearing ring 48produce twice as many contacts or force transmitting points upon therotatable bearing ring 48. The rotatable bearing ring, which may be madefor instance in six or more segmental sections, depending upon the sizeof the preheater, can for reasons of costs be made only of limitedthickness and thus the weight of the rotor is distributed upon arelatively small number of balls 106 along the extension of therotatable bearing ring reckoned from each place of load transmittingcontact. An increase in the number of load transmitting contact pointsresults in that a greater number of balls are carrying the weight of therotor.

The general arrangement of the brackets or fins 68, 84 or and thesegmental sections 108 is preferably such that a symmetricaldistribution of the parts is obtained and the load also is distributedevenly. The resilient means can be utilized to bridge the joints betweenthe segmental sections 108 of the upper bearing ring 48 as for instancethe plate spring 118 in Fig. 4. With the plate springs only located inthis way as bridging means between the ends of the segmental sections103 the Weight of the rotor is transferred to each segmental section viathe brackets or fins 68, 84 and 100 in two places, viz., at the endsthereof.

The arched plate springs 118 engage the rotor brackets or fins 68, 84 or100 at the apex thereof and are provided with guide means in the form ofprojections 120 thereon for registering with the rotor carrying bracketsor fins 68, 84 or 100. Said guide means 120 serve on the one hand asdrivers for the rotatable bearing member and on the other hand as meansto center the rotor upon radial expansion thereof due to heating. Theplate springs may be fixed in peripheral direction relative to thebearing ring segmental sections 108 by means of stop pins or bolts orscrews 122 fastened to the segmental sections. Owing to its design theplate spring is easily removable and for such purpose a segmentalelement of the ring 50 is removed for dismantling of a bearing section.When the segmental ring element is removed the plate spring 113 can bedrawn out by means of a suitable tool and a segmental section 108 of theupper bearing ring 48 may then be removed Without lifting of the rotor.After mounting of the segmental section of the upper bearing ring theplate spring is forced into position and the segmental ring element isreinserted.

The structure just described provides numerous important advantages withrespect to both initial cost and upkeep. As to the former, the use ofthe wire elements 104 to provide the tracks for the balls eliminates theneed for providing finely finished surfaces forming the recesses 102 and110. The wire elements themselves are very inexpensive, advantageouslybeing made of piano wire or other high carbon or steel like metal ofsimilar elastic nature. Balls 106 are advantageously of the kind used instandard ball bearings and also may be relatively inexpensive since theaction of the bearing is such that a high degree of precision in theparts is not required and balls rejected for use in ordinary ballbearings because of failure to meet dimensional tolerances may readilybe used. The reason for this is that the number of balls employed inrelation to the weight carried is such that the balls deform the wirerails sufiiciently to create narrow tracks on the rails, and theelasticity of the metal of the rails and of the balls themselves issulficient to compensate for minor dimensional variations. The elasticdeformation that is possible with the construction described alsoinsures even distribution of the weight carried by the hearing. Suchconstruction is made practically possible because of the fact that inapparatus of the kind under consideration the speed of rotation of therotors is only a very few revolutions per minute, so that even in thecase of relatively very large diameter rotors, the linear; speed ofoperation of the bearing is very low as compared with usualanti-friction bearing applications. Wear is thus very slow particularlysince temperature conditions may be controlled so that the bearing mayreadily be grease lubricated. Because of the anti-friction nature of thebearing, power consumption is very low.

By virtue of the manner in which the tracks or rails are formed on therails by the action of the bearing itself, sections or segments of therails and also individual balls that become unduly worn or otherwisedefective can readily be replaced and this is easily accomplishedbecause of the removable segmental construction of the parts t and 108giving access from the exterior of the casing to the balls and rails. Inthe construction shown, balls and rail segments can be removed While thebearing is under load.

It will be evident that the bearing construction is such that not onlyis the lower bearing member 46 (Fig. 1) fixed both radially and axiallywith respect to the end plate 12, but also the upper bearing member 48which is radially fixed by the balls 106. The pins 112 are thus fixedwith respect to the stationary structure carrying the driving gear 114which enables simple and inexpensive forms of gearing to be used andalso makes the apparatus adaptable for friction drive.

The fixed position of the bearing member 48 axially relative to the endplate 12 (Fig. l) is highly important from the standpoint of efiectivesealing, since it maintains the end of the outer rotor shell located insubstantially fixed relation axially with respect to the adjacent endplate regardless of dishing or other distortion of the rotor caused bytemperature dilferentials. As the sealing means form no part of thisinvention reference may be had to our copending patent application Ser.No. 349,344, now U.S. Patent No. 2,936,160 granted May 10, 1960, for thearrangement of appropriate seals and the details of constructionthereof. Peripheral and radial seals are shown schematically in thedrawings and are denoted 124 and 126, respectively, in Fig. 8. Thelatter seals may be attached between the radial sides of contiguousbaskets.

The casing encircling the rotor may be provided with a door 128 foraccess to the rotor from the exterior and of sufficient width to permitremoval and replacement of a basket of the basket assembly constitutingthe rotor. In Fig. 5 the door 128 is a removable section of the shell 40and the joints between the door section of the shell and the rest of theshell are closed by strips 130.

In the preheater according to Fig. 9 the baskets 54 are provided withflange like projections 132 projecting horizontally outwardly and eachforming a segmental section of a continuous annular flange surroundingthe outer wall of the rotor, said outer wall comprising abutting areshaped ends 134 of abutting baskets. By means of this annular flange therotor is carrier on a bearing of the character described above. Fig. 9also shows alternatively that the flange of the rotor instead of theupper rotatable member of the bearing is provided with the rack of theperipheral drive pins 112.

In the construction shown in Figs. 3 and 6 with the rotor made in twoportions which may be filled with regenerative elements of dilferentmaterial, for instance one of the portions consisting of a more heatresisting material than the other.

From the foregoing it will be obvious that the principles of theinvention may be carried into effect by means of a wide variety ofspecific structural embodiments, that various features maybe combined indifren ent ways and that certain features may be employed to theexclusion of others. The invention is accordingly to be understood asembracing all forms of apparatus falling within the scope of theappended claims.

What we claim is:

1. A rotary heat exchanger comprising vva rotor com- 35 ponent, astationary component including apertured end plates the apertures ofwhich define paths of flow of differentheat-exchanging media and bearingmeans for rotatably supporting the rotor component at the outerperiphery thereof with respect to the stationary component, said rotorcomponent constituting a coherent unit comprising a plurality ofsector-shaped baskets positioned in abutting relationship around theaxis of the device so that the radial sides of contiguous baskets de-.fine partitions extending radially from the inner to the outer peripheryof the rotor component, the inner and the outer Walls of the rotorcomponent being comprised of abuttingtransverse ends of abuttingbaskets, the radial sides of contiguous baskets being fastened togetherwhereby the assembly of said baskets alone forms a completely coherentrotor the inner and outer circumferential walls of which are formed bythe transverse ends of the baskets, each of said baskets being providedwith means for supporting the same on said bearing means.

2. A rotary heat exchanger as claimed in claim 1, in which the rotorcomponent is suspended on the bearing means.

3. A rotary heat exchanger as claimed in claim 2, in which the rotorcomponent is suspended at the top end thereof.

4. A rotary heat exchanger as claimed in claim 1, in which the rotorcomponent is carried by the bearing means.

5. A rotary heat exchanger as claimed in claim 4, in which the rotorcomponent is carried at the lower end thereof.

6. A rotary heat exchanger comprising a rotor component, a stationarycomponent including apertured end plates the apertures of which definepaths of flow of different heat-exchanging media and bearing means forretatably supporting the rotor component at the outer periphery thereofwith respect to the stationary component, said rotor componentcomprising a plurality of sector shaped baskets positioned in abuttingrelationship around the centre of the rotary device so that the radialsides of contiguous baskets define partitions extending radially fromthe inner to the outer periphery of the rotor component and the innerand outer walls of the rotor component comprise abutting transverse endsof abutting baskets, whereby said rotor component is formed solely bysaid baskets, and said bearing means comprising two bearing memberscoaxial with the rotor component, a first one of said bearing membersbeing associated with said rotor component and mounted to rotatetherewith, the outer transverse end wall of each of said baskets beingprovided with a radially extending substantially horizontal flangesupported on said first one of said hearing members, a second one ofsaid bearing members being associated with said stationary component androtationally stationary therewith, and one of said bearing members andthe component with which it is associated being relatively movablelaterally with respect to each other.

7. A rotary device as claimed in claim 6, in which the flanges of thebaskets are provided with driving means for peripheral drive of therotor component.

8. A rotary heat exchanger as claimed in claim 6, in which the bearingmember associated with the rotor component is provided with drivingmeans for peripheral drive of the rotor component.

9. A rotary heat exchanger as claimed in claim 6, in which the bearingmeans comprises a lower stationary supporting member having an annularrecess on the upper side thereof coaxial with the rotor component, anupper rotatable member supporting the rotor and having an annular recesson the under side thereof adapted to register with the annular recess inthe stationary supporting member, mcuate lengths of wire located in thecorners of said annular recesses, and anti-friction bearing elementsengaged in rolling contact with the lower and upper rails provided bysaid arcuate lengths of wire located in said annular recesses.

10. A rotary heat exchanger as claimed in claim 9, in which at least oneof the bearing members is made up of a plurality of relatively movablesegmental sections permitting radial enlargement and contraction of thehearing member.

11. A rotary heat exchanger comprising within a stationary casingincluding apertured' end plates the apertures of which define paths offlow of different heat-exchanging media a rotor component made up of aplurality of sector shaped baskets provided with at least one radiallyextending bracket means each and positioned in abutting relationshiparound the centre of the rotary device so that the radial sides ofcontiguous baskets define partitions extending radially from the innerto the outer periphery of the rotor and the inner and the outer walls ofthe rotor comprise abutting transverse ends of abutting baskets; wherebysaid rotor component is formed solely by said baskets, a ball bearingconstruction including a lower stationary supporting memher having araceway on the upper side thereof coaxial with the rotor component, anupper rotatable member having a raceway on the under side thereofadapted to register with the raceway in the stationary member,antifriction bearing elements in said raceways for maintaining themembers in axially spaced relation, the bracket means being supported atcircumferentially spaced places by the rotatable bearing member in orderto sustain the weight of the rotor component by the plurality of bracketmeans supported on the rotatable bearing member.

12. A rotary heat exchanger as claimed in claim 11, in which the bracketmeans comprise radially extending vertical fins.

13. A rotary heat exchanger as claimed in claim 12, in which the outerwall of each basket is provided with a radially extending vertical finadjacent each radial side of the basket.

14. A rotary heat exchanger as claimed in claim 13, in which the bracketmeans comprise radial extensions of the abutting radial sides ofcontiguous baskets.

15. A rotary heat exchanger as claimed in claim 13, in which a pluralityof circumferentially spaced resilient supporting means rest on therotatable bearing member and are adapted to register each with a pair ofvertical fins extending radially adjacent the abutting radial sides ofcontiguous baskets in order to sustain the weight of the rotor componentby the plurality of said pairs of vertical fins resiliently supported onthe rotatable bearing member.

:16. A rotary heat exchanger as claimed in claim 12, in which the upperrotatable bearing member comprises a plurality of circumferentiallyspaced segmental sections, each of which supports at least one of thevertical fins for sustaining the rotor component.

17. A rotary heat exchanger as claimed in claim 15, in which theresilient supporting means bridge the joints between the segmentalsections of the upper rotatable member.

18. A rotary heat exchanger as claimed in claim 17, in which theresilient supporting means comprise arched plate springs and in whichmeans are provided on the segmental sections of the upper rotatablebearing memher to fix the position of the arched plate springs thereonand to maintain said segmental sections in their circumferentiallyspaced relationship.

19. A rotary heat exchanger comprising a rotor component, a stationarycomponent including apertured end plates the apertures of which definepaths of flow of difierent heat-exchanging media and bearing means forrotatably supporting the rotor component at the outer periphery thereofwith respect to the stationary component, said rotor componentcomprising two superimposed portions, a first portion of which comprisesa structural plate framework supported by said bearing means and thesecond portion of which comprises a basket structure supported by saidfirst portion and comprising a plurality of sector shaped basketspositioned in abutting relationship around the centre of the rotarydevice so that the radial sides of contiguous baskets define partitionsextending radially from the inner to the outer periphery of the rotorcomponent and the inner and the outer walls of the rotor componentcomprise abutting transverse ends of abutting baskets.

20. A rotary heat exchanger as claimed in claim :19, in which thestructural plate framework comprises a spoke wheel, the hub and rimportions of which register with the inner and outer walls, respectively,of the basket structure of the rotor component and the spokes of whichregister with the radially extending partitions of the basket structure.

21. A rotary heat exchanger as claimed in claim 20, in which the spokesextend beyond the outer periphery of the rotor component as bracketmeans to carry the rotor component on the peripherally disposed bearingmeans.

22. A rotary heat exchanger as claimed in claim 20, in which the spokewheel forms the lower portion of the rotor component and the baskets arecarried upon the spoke wheel.

23. A rotary heat exchanger as claimed in claim 20, in which the spokewheel forms the upper portion of the rotor component and the baskets aresuspended in the spokes of the spoke wheel.

24. A rotary heat exchanger as claimed in claim 19, in which at leastthe basket structure portion of the rotor component is filled withregenerative elements.

25. A rotary heat exchanger as claimed in claim 24, in which also thestructural plate framework portion is filled with regenerative elements.

26. A rotary heat exchanger as claimed in claim 25, in which theregenerative elements in the two portions of the rotor are made up ofdiiferent materials.

27. A rotary heat exchanger as claimed in claim 6, in which thestationary component comprises a casing encircling the rotor and beingprovided with door means for access to the rotor component from theexterior.

References Cited in the file of this patent UNITED STATES PATENTS2,432,198 Karlsson et al. Dec. '9, 1947 2,549,583 Eckersley Apr. 17, -1

FOREIGN PATENTS 758,672 Germany Nov. 2, 1944 1,082,683 France Dec. 31,1954

